Shackle for drills, &amp;c.



M. W. SHERWOOD. SHACKLE FOR DRILLS, 6co- APPLICATION FILED Nov.24, I9I3.

Patented Sept; 28, 1915.

a4! do; a r' "'I, e?

W25 MQQ/L W of the lower end of a hammer drill embody: ing my invention, showing a portion of the tionr is provided bymean's of .abolt 411 which passes freely throughithe-opening 10 zinone s. end ofithe bargand whosefhead bears against the lower face; of tllbitl'l and ithereby supex ports the lattertkf As; shownta'nd by: prefer? MATHER w. SHERWOOD, or FRANKLIN, PEN SYLVANI ,assie ronfmofciiiciieo j PNEUMATIC TOOL COMPANY, OF CHICAGO, ILLINOIS, A coiaronhrion onnsw JERSEY.

To all whom it may concern:

Be it known that I, MATHER W. Sirenwool), a citizen of theUnited States, residing at Franklin, Venango county, Pennsylvania, have invented a certain new and use. ful Shackle for Drills, &c., of which the following is a specification. v v j My invention relates to means for holding the bits or steel of drills and similar machines and the object thereof is to pro-,

vide a simple, etiicient and reliable means for this purpose. In using a hammer drill it is often desirable to have the bits secured to the machine in such a manner as to permit of its unrestricted movement in response to the blows dealt by the hammer and yet been employed to accomplish this result but in all cases it is necessary to provide the bit or steel with a collar, maklngthe bit more expensive than when provided with a plain shank, besides which the means for holding such special form of bit was more or less complicated and cumbersome and.

did not permit of the ready removal of such bit. In the case of my holding means, which is in the form of a shackle, a plain bit of the usual construction is employed:

andthe same is readily insertible or remov able and is permitted the necessary movement in the operation of the machine.

In the drawing, Figure lqis an elevation dr'ill socket and adjacent parts in section 3 and Fig. 2 a' similar view illustrating at 40 modified form of construction:

My invention may be embodied in drilling machines, of diiferent constructionsand. in the present instance I have shown the.

same used in connection with. a machine of the hammer drill type in which. a reciprocat-- ing piston delivers itsbloweither directly upon the inner end of the'drill bit or steel or indirectly through a striking piece; or anvil. Inasmuch as only thefront or lower 1 end of the machine is concernedywith an. understanding of my invention, I have shown such portion only.

Referring to the embodiment-of vention illustrated in Fig. l, the frontend of the cylinder'l has-coupled or joined to SHACKLE FOR mums, 85c.

Specification of Letters Patent.

it the fronthead or socket. in a suitable manner as by means of the front s ITED STATES-PATENT r mmed-s ems,19115. Application filed Novemberai, 191a. SerialNo. 802,719. ii

head bolts 3 passing, through thelugs 4: and e v .5 on the cylinder and socket" respectively. These bolts serve to holdthe socketto the.

front or lower head withjayielding pressure by reason of the coiledsprings .6 Eencircling'y the bolts between their-headsand the lug 5, nuts 7 screwingonthe upperendsioi the It \Vlll be understood, that there. are

bolts.

two of these bolts and associated parts although only one. set .is shownin Fig. 1. I

The socket member-or drill socket'is pro-=- I vided with a central bore to receive the inner or upper end ofrthe drill bit or steel 8 which, in the present instance, ispolygonal or angular in cross section. This bit projects inwardly and receives blows delivered by the piston (not-shown) but in the present instance theblowsjare delivered to the bit in an indirectmanner through the as is illustrated in Fig.2 andgwhichlmay medium of a strikingpiece or, anvil 9, such be employed in the construction shown in I Fig. 1.

It will be observed that the .bit is a plain bit of the usual commercial, form,

that is, having a shank oi -uniform size,

throughout its length. a

My shackle meanscomprisesa bar. 10 of "suitable shape and dimensions and having intermediate its length ahole 10% which is of a size to fit fairly close upo'ii theibit... This thereupon I and also 1 be permitted" the proper qbar has a loose pivotal "COIIDQCtlOIIYWlth the; drill socket in order thatitsmayberetained movements hereinafter explained. In the I present instance this rloose'zlpivotal connec f R ence, the bar is countersunk at the outer or lower end of the hole 19* to: f ceivevthe icor- 3? respondingly shaped'-;headiof.': the-bolt; This .1

bolty passes upwardlym'through ea? springii' chamber 12 formed in the body-inf the'socketri: and v is provided, at a its"? upper end! with .Ja'T sleeve l3 adapted ftor; fit? and "slideu QIlIIl "the:

upper end ;of the .(zhainberrilQwA i-nut 14a;

screws; upon "the. .uppereeiidsxofethe bolt?) and:

piston 18 adapted to fit and slide in the chamber 17 and to be projected through the lower end thereof into contact with the upper surface of the bar 10 by means of the coiled spring 19 hearing at one end against the outer end of the piston and its upper end against the top of the chamber 17. The bolt 16 is provided at its upper end with a nut 20.

The tendency of the spring 19 is to force the piston 18outwardly and to thereby move or cant the bar 10 in such a manner as to grip and hold the bit by frictional engagement. In this movement of .the shackle or bar by means of the spring 19 one'end of such bar, that is the right hand end in Fig.

1, is moved downwardly and the bit gripped as explained, and the downward movement of the oppositeend of the bar or shackle is resisted by the yielding support provided by the bolt 11. The spring 15 which is associated with this bolt is interposed to afford suflicient resiliency so as to permit of a slight forward movement of the bit when the blow is struck by the hammer and to prevent the shackle itself from sustaining a part of the force of the blow which would result from a rigid support at that point. The downward movement of this end of the bar or shackle is limited by means of the flangev or collar 13 of the sleeve 13 which is adapted to come into contact with the top of the chamber 12. This arrangement prevents undue strain upon the spring 15 and also prevents'such forward movement of the bar or shackle as would too greatly diminish the l pressure exerted by the other spring 19 when the machine is lifted to withdraw the bit from the hole. It is obvious that bypulling upwardly on the end of the bar or shackle 10 by means of the hand the spring 19 will'be compressed and the bit will be released.

It will be understood that the bolt 16 is not essential but-is provided merelyas a guide'to keep the shackle or bar in positiofi and to prevent undue displacement by the action of the spring 19 when the bit is removed from the socket.

In Fig. 2 I have shown a modified form of embodiment of my invention according to which the. front headbolts are utilized to support the shackle, thereby dispensing with the separate bolts 11 and 16. In this modified form of construction the head bolts 21 'portion with the usual spring 26 bearing at one end against the lug 5 and at its other end against the collar 27 fitting upon the bolt.

The other bolt 22 likewise passes through the lugs 4.- and 5 and is provided with a similar coiled spring 26 and a collar 27. Between this collar and an end of the shackle or bar 23 is interposed a spring 28 which has the same action upon the. bar as the spring 19 of the first described form. If desired, the shackle may be provided on one or both sides with flanges or wings 23 in order to add lateral support to the bolts 21 and 22 which would otherwise be supported only at their engagement with the lugs of the cylin-- der and front head or drill socket through which they pass.

I claim:

1. In combination with a drill socket and a drill bit therein, a spring-pressed tilting gripping member provided with a hole through which said bit passes for frictionally gripping the same.

2. In comblnation with a drill socket and I and a yielding means acting on the bar to cant the same and thereby grip the bit.

4. In combination with a drill socket and a drill bit therein, means for frictionally gripping the bit, comprising a bar pivotally connected at one end with the drill socket and provided in the middle portion with a hole through which the bit passes, and a yielding means acting on the other end of the bar to cant .the same and thereby grip the bit.

5. In combination with a drill socket and a drill bit therein, means for frictionally' gripping. the bit comprising a bar provided with a hole through which the bit passes, a

bolt which depends from the drill socket and on which one end of the bar is pivoted,

yielding means acting on the other" anda end thereof to cant the same and thereby;

grip the bit.

p c. In combination with adrill socket and 55 and 22 pass through the lugs 4 and 5 and a drill bit therein, means [for frictionally 0 gripping the bit comprising a bar provided with a hole through which the bit passes, a'

7. In combination with a drill socket and a drill bit therein, means for frictionally gripping the bit comprising a bar provided with a hole through which'the bit passes,v

said socket having openings on opposite sides, a bolt arranged in one of the openings and engaging one end of the bar, and a yielding member arranged in the other opening and bearing against the adjacent end of the bar. 1

8. In combination with a drill socket and a drill bit therein, means for frictionally gripping the bit comprising a bar provided with a hole through which-the bit passes, said socket having openings on opposite sides, a-bolt arranged in one of the openings and engaging one end of the bar, and a spring-pressed plunger in the otheropening arranged to bear against the adjacent end of the bar.

9. In combination with a drill socket and a drill bit therein, means for frictionally gripping the bit comprising a bar provided with a hole through which the bit passes, said socket having openings on opposite sides, a bolt arranged in one of the openings and engaging one end of the bar, a spring pressed plunger in the other opening arranged to bear against the adjacent end of the bar, and a bolt passing through the plunger and engaging the bar.

10. In combination with a drill having a socket member and a drill bit slidingly mounted therein, means for frictionallv gripping the 'bit comprising a bar provided with a hole through which the bit passes, a spring-pressed bolt also mounted in the socket member and loosely engaging one end of the bar, and a spring pressed plunger also mounted in the socket member and hearing against the other end of the bar.

11. In combination with a drill socket and a drill bit therein, means for frictionally gripping the bit and yieldingly supporting it comprising a tilting gripping member provided with a hole through which the bit passes, a pivotal support for one end of said tilting member yieldingly connected to the drill socket, and spring means connected to the other end of said tilting member and also connected to the drill socket for tilting said member to frictionally grip the bit.

MATHER W. SHERWOOD.

Witnesses: i

W. H. CALLAN, R. G. CRowDnR. 

